From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1285) id 5D686385800A; Fri, 14 Oct 2022 09:58:41 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 5D686385800A DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1665741521; bh=ki5OJkm1r45N2++vYYzweJFZ4y+uMU84SVK4FdCbKcA=; h=From:To:Subject:Date:From; b=bPgxWh5V3Bjhw59LffZ3z5VoE5xaMWAaq57Hpc1IbwhL0+oSLBbvZc+ZjZlMkCVsJ ugM2qN3IZsysOdE7HBEmz7omACMiAlc94lhGJCVlTzY+8rnaWFEkvDgGH7UAzYUS42 dJwBsjbxlBa0MMgaJkn4UoOuJgFw5drOY5RPdPmI= MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Eric Botcazou To: gcc-cvs@gcc.gnu.org Subject: [gcc r11-10311] Fix PR target/107248 X-Act-Checkin: gcc X-Git-Author: Eric Botcazou X-Git-Refname: refs/heads/releases/gcc-11 X-Git-Oldrev: 35840348841d1b948cf206fc324373e08f36fcea X-Git-Newrev: 3f4b65df625edae3e8829718af721ad2330b3f22 Message-Id: <20221014095841.5D686385800A@sourceware.org> Date: Fri, 14 Oct 2022 09:58:41 +0000 (GMT) List-Id: https://gcc.gnu.org/g:3f4b65df625edae3e8829718af721ad2330b3f22 commit r11-10311-g3f4b65df625edae3e8829718af721ad2330b3f22 Author: Eric Botcazou Date: Fri Oct 14 11:52:04 2022 +0200 Fix PR target/107248 This is the infamous PR rtl-optimization/38644 rearing its ugly head for leaf functions on SPARC more than a decade later... Richard E.'s generic solution has never been implemented so let's do as other RISC back-ends did. gcc/ PR target/107248 * config/sparc/sparc.c (sparc_expand_prologue): Emit a frame blockage for leaf functions. (sparc_flat_expand_prologue): Emit frame instead of full blockage. (sparc_expand_epilogue): Emit a frame blockage for leaf functions. (sparc_flat_expand_epilogue): Emit frame instead of full blockage. Diff: --- gcc/config/sparc/sparc.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) diff --git a/gcc/config/sparc/sparc.c b/gcc/config/sparc/sparc.c index e4fe2f065c9..a9196d68863 100644 --- a/gcc/config/sparc/sparc.c +++ b/gcc/config/sparc/sparc.c @@ -6122,6 +6122,9 @@ sparc_expand_prologue (void) } RTX_FRAME_RELATED_P (insn) = 1; + + /* Ensure no memory access is done before the frame is established. */ + emit_insn (gen_frame_blockage ()); } else { @@ -6136,13 +6139,7 @@ sparc_expand_prologue (void) /* %sp is not the CFA register anymore. */ emit_insn (gen_stack_pointer_inc (GEN_INT (4096 - size))); - /* Make sure no %fp-based store is issued until after the frame is - established. The offset between the frame pointer and the stack - pointer is calculated relative to the value of the stack pointer - at the end of the function prologue, and moving instructions that - access the stack via the frame pointer between the instructions - that decrement the stack pointer could result in accessing the - register window save area, which is volatile. */ + /* Likewise. */ emit_insn (gen_frame_blockage ()); } else @@ -6238,8 +6235,8 @@ sparc_flat_expand_prologue (void) } RTX_FRAME_RELATED_P (insn) = 1; - /* Ensure nothing is scheduled until after the frame is established. */ - emit_insn (gen_blockage ()); + /* Ensure no memory access is done before the frame is established. */ + emit_insn (gen_frame_blockage ()); if (frame_pointer_needed) { @@ -6326,6 +6323,9 @@ sparc_expand_epilogue (bool for_eh) ; /* do nothing. */ else if (sparc_leaf_function_p) { + /* Ensure no memory access is done after the frame is destroyed. */ + emit_insn (gen_frame_blockage ()); + if (size <= 4096) emit_insn (gen_stack_pointer_inc (GEN_INT (size))); else if (size <= 8192) @@ -6376,15 +6376,15 @@ sparc_flat_expand_epilogue (bool for_eh) ; /* do nothing. */ else if (frame_pointer_needed) { - /* Make sure the frame is destroyed after everything else is done. */ - emit_insn (gen_blockage ()); + /* Ensure no memory access is done after the frame is destroyed. */ + emit_insn (gen_frame_blockage ()); emit_move_insn (stack_pointer_rtx, gen_rtx_REG (Pmode, 1)); } else { /* Likewise. */ - emit_insn (gen_blockage ()); + emit_insn (gen_frame_blockage ()); if (size <= 4096) emit_insn (gen_stack_pointer_inc (GEN_INT (size)));